Quote Originally Posted by bowtie427ss View Post
IMO, an important detail to keep in mind is the thickness of the cell walls where the cells will come together at their throats. Ideally, each cell will need to be carefully sanded at the throat end to a thickness as close as possible to the thickness of the tin. The better sounding multicells i've heard(and i've only heard a few) had been carefully hand sanded to a nearly knife edge at the throat junction such that there's no surface left to reflect energy back toward the driver.
That's why I was thinking 10 ply 3/16 plywood. Each ply would be <.02" thick. You could work that pretty fine an since it's enclosed in the flange, it is not really subject to damage. A small wedge of folded aluminum flashing on can even be fared into the ends without majot hassle.